Overshooting
Movement beyond the normal limits of a bird's area of distribution by continuance in the usual direction of migration beyond the proper destination. By this means birds which are not normally found any further north than the Mediterranean region may reach the British Isles, for example the Black-eared Wheatear Oenanthe hispanica and the Subalpine Warbler Sylvia cantillans.From Peter Weaver's Birdwatcher's Dictionary
Copyright © 1981 by Peter Weaver